The kits that I've seen advertised are for converting an automatic to a four speed. They are expensive, and contain a bunch of parts that you won't need since you already have a floor shifted manual car. But they may make a kit up for you that would only contain what you need, and would be much cheaper than an auto to manual conversion kit. Brewers would be a good place to start - www.brewersperformance.com

If there are any decent Mopar swap meets in your area, though, you could save a ton of money getting what you need there. That would require waiting until the swap meet, though, so if you're dead set on doing it now, that won't work. You might also be able to find what you need on you local Craig's List, or find a person near you selling what you need on Ebay (buying locally with Craig's list or Ebay would give you the chance to inspect it before buying). You might want check out the for sale section here on Moparts too. But if you want parts that are new, or in like-new condition, Brewers would be the place to go. Their transmissions have a 12 month warranty too, so that's another thing to consider.